Problem with too many faces of object
It's generally bad practice to make the colors directly dependent on the topology of the object (there are exceptions, of course).

Instead you should use a Texture.

A texture is usually an image which is mapped to the surface of your object based on a UV map. There are other kinds of textures and mapping techniques as well, e.g. Procedural textures.
However, in this case you probably want to UV unwrap and use an image texture.

For example, I can UV unwrap this sphere:

 

and then texture it with this image:



Result:



As you can see, the texture is not dependent on the topology of the mesh.

I recommend you check out some tutorials on texturing and UV unwrapping in blender. There are many good sources out there (google is your friend), but here are a couple of places to start with:


Blender Cookie
Blender Guru
The Blender wiki


Also check the beginner's reference on meta.